Stroke for the American Board of Internal Medicine (ABIM) Exam

• Ischemic Stroke: Most common type (85%), caused by the obstruction of a blood vessel supplying blood to the brain.
• Hemorrhagic Stroke: Caused by bleeding into or around the brain (15% of strokes).

• Pathophysiology:
• Thrombotic Stroke: Formation of a clot within a cerebral artery, often associated with atherosclerosis.
• Embolic Stroke: A clot or other debris forms in another part of the body (often the heart) and moves to the brain.

• Modifiable: Hypertension, atrial fibrillation, diabetes mellitus, smoking, dyslipidemia, sedentary lifestyle.
• Non-modifiable: Age, gender, family history of stroke, genetic predisposition.

• Symptoms:
• Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body.
• Confusion, trouble speaking, or difficulty understanding speech.
• Trouble seeing in one or both eyes.
• Trouble walking, dizziness, loss of balance, or lack of coordination.
• Severe headache with no known cause.

See Stroke Syndromes for detailed presentations.

• Initial Assessment:
• Use of the NIH Stroke Scale to evaluate and quantify the severity of the stroke.
• Imaging:
• Non-contrast CT Scan: First-line imaging to rule out hemorrhagic stroke and identify early signs of ischemia.
• MRI: More sensitive for detecting ischemic stroke, especially in the posterior fossa.

• Acute Treatment:
• Ischemic Stroke: IV thrombolysis with alteplase (tpa) or tenecteplase (TNK) if within 4.5 hours of onset, following exclusion of hemorrhage via CT.
• Endovascular Thrombectomy: For eligible patients with large vessel occlusions within 6 to 24 hours of last known normal.
• Supportive Care: Management of blood pressure, fluids, electrolytes, and fever.
• Secondary Prevention:
• Antiplatelet therapy (aspirin, clopidogrel) (single or dual antiplatelet therapy) or anticoagulants for atrial fibrillation or cardiac thrombus.
• Statins for atherosclerotic disease.
• Lifestyle modifications.

• Management of Acute Stroke: Timing and selection of therapeutic interventions like thrombolysis and thrombectomy.
• Differentiation of Stroke Types: Distinguishing between ischemic and hemorrhagic stroke based on clinical presentation and imaging.
• Preventive Strategies: Focus on risk factor management and the role of anticoagulation in atrial fibrillation.
• Post-Stroke Care: Recognition and management of complications, including rehabilitation and addressing secondary prevention measures.